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diff --git a/install/ui/util/uglifyjs/lib/consolidator.js b/install/ui/util/uglifyjs/lib/consolidator.js new file mode 100644 index 000000000..68169b375 --- /dev/null +++ b/install/ui/util/uglifyjs/lib/consolidator.js @@ -0,0 +1,1219 @@ +/** + * @preserve Copyright 2012 Robert Gust-Bardon <http://robert.gust-bardon.org/>. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER "AS IS" AND ANY + * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE + * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, + * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR + * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR + * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF + * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +/** + * @fileoverview Enhances <a href="https://github.com/mishoo/UglifyJS/" + * >UglifyJS</a> with consolidation of null, Boolean, and String values. + * <p>Also known as aliasing, this feature has been deprecated in <a href= + * "http://closure-compiler.googlecode.com/">the Closure Compiler</a> since its + * initial release, where it is unavailable from the <abbr title= + * "command line interface">CLI</a>. The Closure Compiler allows one to log and + * influence this process. In contrast, this implementation does not introduce + * any variable declarations in global code and derives String values from + * identifier names used as property accessors.</p> + * <p>Consolidating literals may worsen the data compression ratio when an <a + * href="http://tools.ietf.org/html/rfc2616#section-3.5">encoding + * transformation</a> is applied. For instance, <a href= + * "http://code.jquery.com/jquery-1.7.1.js">jQuery 1.7.1</a> takes 248235 bytes. + * Building it with <a href="https://github.com/mishoo/UglifyJS/tarball/v1.2.5"> + * UglifyJS v1.2.5</a> results in 93647 bytes (37.73% of the original) which are + * then compressed to 33154 bytes (13.36% of the original) using <a href= + * "http://linux.die.net/man/1/gzip">gzip(1)</a>. Building it with the same + * version of UglifyJS 1.2.5 patched with the implementation of consolidation + * results in 80784 bytes (a decrease of 12863 bytes, i.e. 13.74%, in comparison + * to the aforementioned 93647 bytes) which are then compressed to 34013 bytes + * (an increase of 859 bytes, i.e. 2.59%, in comparison to the aforementioned + * 33154 bytes).</p> + * <p>Written in <a href="http://es5.github.com/#x4.2.2">the strict variant</a> + * of <a href="http://es5.github.com/">ECMA-262 5.1 Edition</a>. Encoded in <a + * href="http://tools.ietf.org/html/rfc3629">UTF-8</a>. Follows <a href= + * "http://google-styleguide.googlecode.com/svn-history/r76/trunk/javascriptguide.xml" + * >Revision 2.28 of the Google JavaScript Style Guide</a> (except for the + * discouraged use of the {@code function} tag and the {@code namespace} tag). + * 100% typed for the <a href= + * "http://closure-compiler.googlecode.com/files/compiler-20120123.tar.gz" + * >Closure Compiler Version 1741</a>.</p> + * <p>Should you find this software useful, please consider <a href= + * "https://paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=JZLW72X8FD4WG" + * >a donation</a>.</p> + * @author follow.me@RGustBardon (Robert Gust-Bardon) + * @supported Tested with: + * <ul> + * <li><a href="http://nodejs.org/dist/v0.6.10/">Node v0.6.10</a>,</li> + * <li><a href="https://github.com/mishoo/UglifyJS/tarball/v1.2.5">UglifyJS + * v1.2.5</a>.</li> + * </ul> + */ + +/*global console:false, exports:true, module:false, require:false */ +/*jshint sub:true */ +/** + * Consolidates null, Boolean, and String values found inside an <abbr title= + * "abstract syntax tree">AST</abbr>. + * @param {!TSyntacticCodeUnit} oAbstractSyntaxTree An array-like object + * representing an <abbr title="abstract syntax tree">AST</abbr>. + * @return {!TSyntacticCodeUnit} An array-like object representing an <abbr + * title="abstract syntax tree">AST</abbr> with its null, Boolean, and + * String values consolidated. + */ +// TODO(user) Consolidation of mathematical values found in numeric literals. +// TODO(user) Unconsolidation. +// TODO(user) Consolidation of ECMA-262 6th Edition programs. +// TODO(user) Rewrite in ECMA-262 6th Edition. +exports['ast_consolidate'] = function(oAbstractSyntaxTree) { + 'use strict'; + /*jshint bitwise:true, curly:true, eqeqeq:true, forin:true, immed:true, + latedef:true, newcap:true, noarge:true, noempty:true, nonew:true, + onevar:true, plusplus:true, regexp:true, undef:true, strict:true, + sub:false, trailing:true */ + + var _, + /** + * A record consisting of data about one or more source elements. + * @constructor + * @nosideeffects + */ + TSourceElementsData = function() { + /** + * The category of the elements. + * @type {number} + * @see ESourceElementCategories + */ + this.nCategory = ESourceElementCategories.N_OTHER; + /** + * The number of occurrences (within the elements) of each primitive + * value that could be consolidated. + * @type {!Array.<!Object.<string, number>>} + */ + this.aCount = []; + this.aCount[EPrimaryExpressionCategories.N_IDENTIFIER_NAMES] = {}; + this.aCount[EPrimaryExpressionCategories.N_STRING_LITERALS] = {}; + this.aCount[EPrimaryExpressionCategories.N_NULL_AND_BOOLEAN_LITERALS] = + {}; + /** + * Identifier names found within the elements. + * @type {!Array.<string>} + */ + this.aIdentifiers = []; + /** + * Prefixed representation Strings of each primitive value that could be + * consolidated within the elements. + * @type {!Array.<string>} + */ + this.aPrimitiveValues = []; + }, + /** + * A record consisting of data about a primitive value that could be + * consolidated. + * @constructor + * @nosideeffects + */ + TPrimitiveValue = function() { + /** + * The difference in the number of terminal symbols between the original + * source text and the one with the primitive value consolidated. If the + * difference is positive, the primitive value is considered worthwhile. + * @type {number} + */ + this.nSaving = 0; + /** + * An identifier name of the variable that will be declared and assigned + * the primitive value if the primitive value is consolidated. + * @type {string} + */ + this.sName = ''; + }, + /** + * A record consisting of data on what to consolidate within the range of + * source elements that is currently being considered. + * @constructor + * @nosideeffects + */ + TSolution = function() { + /** + * An object whose keys are prefixed representation Strings of each + * primitive value that could be consolidated within the elements and + * whose values are corresponding data about those primitive values. + * @type {!Object.<string, {nSaving: number, sName: string}>} + * @see TPrimitiveValue + */ + this.oPrimitiveValues = {}; + /** + * The difference in the number of terminal symbols between the original + * source text and the one with all the worthwhile primitive values + * consolidated. + * @type {number} + * @see TPrimitiveValue#nSaving + */ + this.nSavings = 0; + }, + /** + * The processor of <abbr title="abstract syntax tree">AST</abbr>s found + * in UglifyJS. + * @namespace + * @type {!TProcessor} + */ + oProcessor = (/** @type {!TProcessor} */ require('./process')), + /** + * A record consisting of a number of constants that represent the + * difference in the number of terminal symbols between a source text with + * a modified syntactic code unit and the original one. + * @namespace + * @type {!Object.<string, number>} + */ + oWeights = { + /** + * The difference in the number of punctuators required by the bracket + * notation and the dot notation. + * <p><code>'[]'.length - '.'.length</code></p> + * @const + * @type {number} + */ + N_PROPERTY_ACCESSOR: 1, + /** + * The number of punctuators required by a variable declaration with an + * initialiser. + * <p><code>':'.length + ';'.length</code></p> + * @const + * @type {number} + */ + N_VARIABLE_DECLARATION: 2, + /** + * The number of terminal symbols required to introduce a variable + * statement (excluding its variable declaration list). + * <p><code>'var '.length</code></p> + * @const + * @type {number} + */ + N_VARIABLE_STATEMENT_AFFIXATION: 4, + /** + * The number of terminal symbols needed to enclose source elements + * within a function call with no argument values to a function with an + * empty parameter list. + * <p><code>'(function(){}());'.length</code></p> + * @const + * @type {number} + */ + N_CLOSURE: 17 + }, + /** + * Categories of primary expressions from which primitive values that + * could be consolidated are derivable. + * @namespace + * @enum {number} + */ + EPrimaryExpressionCategories = { + /** + * Identifier names used as property accessors. + * @type {number} + */ + N_IDENTIFIER_NAMES: 0, + /** + * String literals. + * @type {number} + */ + N_STRING_LITERALS: 1, + /** + * Null and Boolean literals. + * @type {number} + */ + N_NULL_AND_BOOLEAN_LITERALS: 2 + }, + /** + * Prefixes of primitive values that could be consolidated. + * The String values of the prefixes must have same number of characters. + * The prefixes must not be used in any properties defined in any version + * of <a href= + * "http://www.ecma-international.org/publications/standards/Ecma-262.htm" + * >ECMA-262</a>. + * @namespace + * @enum {string} + */ + EValuePrefixes = { + /** + * Identifies String values. + * @type {string} + */ + S_STRING: '#S', + /** + * Identifies null and Boolean values. + * @type {string} + */ + S_SYMBOLIC: '#O' + }, + /** + * Categories of source elements in terms of their appropriateness of + * having their primitive values consolidated. + * @namespace + * @enum {number} + */ + ESourceElementCategories = { + /** + * Identifies a source element that includes the <a href= + * "http://es5.github.com/#x12.10">{@code with}</a> statement. + * @type {number} + */ + N_WITH: 0, + /** + * Identifies a source element that includes the <a href= + * "http://es5.github.com/#x15.1.2.1">{@code eval}</a> identifier name. + * @type {number} + */ + N_EVAL: 1, + /** + * Identifies a source element that must be excluded from the process + * unless its whole scope is examined. + * @type {number} + */ + N_EXCLUDABLE: 2, + /** + * Identifies source elements not posing any problems. + * @type {number} + */ + N_OTHER: 3 + }, + /** + * The list of literals (other than the String ones) whose primitive + * values can be consolidated. + * @const + * @type {!Array.<string>} + */ + A_OTHER_SUBSTITUTABLE_LITERALS = [ + 'null', // The null literal. + 'false', // The Boolean literal {@code false}. + 'true' // The Boolean literal {@code true}. + ]; + + (/** + * Consolidates all worthwhile primitive values in a syntactic code unit. + * @param {!TSyntacticCodeUnit} oSyntacticCodeUnit An array-like object + * representing the branch of the abstract syntax tree representing the + * syntactic code unit along with its scope. + * @see TPrimitiveValue#nSaving + */ + function fExamineSyntacticCodeUnit(oSyntacticCodeUnit) { + var _, + /** + * Indicates whether the syntactic code unit represents global code. + * @type {boolean} + */ + bIsGlobal = 'toplevel' === oSyntacticCodeUnit[0], + /** + * Indicates whether the whole scope is being examined. + * @type {boolean} + */ + bIsWhollyExaminable = !bIsGlobal, + /** + * An array-like object representing source elements that constitute a + * syntactic code unit. + * @type {!TSyntacticCodeUnit} + */ + oSourceElements, + /** + * A record consisting of data about the source element that is + * currently being examined. + * @type {!TSourceElementsData} + */ + oSourceElementData, + /** + * The scope of the syntactic code unit. + * @type {!TScope} + */ + oScope, + /** + * An instance of an object that allows the traversal of an <abbr + * title="abstract syntax tree">AST</abbr>. + * @type {!TWalker} + */ + oWalker, + /** + * An object encompassing collections of functions used during the + * traversal of an <abbr title="abstract syntax tree">AST</abbr>. + * @namespace + * @type {!Object.<string, !Object.<string, function(...[*])>>} + */ + oWalkers = { + /** + * A collection of functions used during the surveyance of source + * elements. + * @namespace + * @type {!Object.<string, function(...[*])>} + */ + oSurveySourceElement: { + /**#nocode+*/ // JsDoc Toolkit 2.4.0 hides some of the keys. + /** + * Classifies the source element as excludable if it does not + * contain a {@code with} statement or the {@code eval} identifier + * name. Adds the identifier of the function and its formal + * parameters to the list of identifier names found. + * @param {string} sIdentifier The identifier of the function. + * @param {!Array.<string>} aFormalParameterList Formal parameters. + * @param {!TSyntacticCodeUnit} oFunctionBody Function code. + */ + 'defun': function( + sIdentifier, + aFormalParameterList, + oFunctionBody) { + fClassifyAsExcludable(); + fAddIdentifier(sIdentifier); + aFormalParameterList.forEach(fAddIdentifier); + }, + /** + * Increments the count of the number of occurrences of the String + * value that is equivalent to the sequence of terminal symbols + * that constitute the encountered identifier name. + * @param {!TSyntacticCodeUnit} oExpression The nonterminal + * MemberExpression. + * @param {string} sIdentifierName The identifier name used as the + * property accessor. + * @return {!Array} The encountered branch of an <abbr title= + * "abstract syntax tree">AST</abbr> with its nonterminal + * MemberExpression traversed. + */ + 'dot': function(oExpression, sIdentifierName) { + fCountPrimaryExpression( + EPrimaryExpressionCategories.N_IDENTIFIER_NAMES, + EValuePrefixes.S_STRING + sIdentifierName); + return ['dot', oWalker.walk(oExpression), sIdentifierName]; + }, + /** + * Adds the optional identifier of the function and its formal + * parameters to the list of identifier names found. + * @param {?string} sIdentifier The optional identifier of the + * function. + * @param {!Array.<string>} aFormalParameterList Formal parameters. + * @param {!TSyntacticCodeUnit} oFunctionBody Function code. + */ + 'function': function( + sIdentifier, + aFormalParameterList, + oFunctionBody) { + if ('string' === typeof sIdentifier) { + fAddIdentifier(sIdentifier); + } + aFormalParameterList.forEach(fAddIdentifier); + }, + /** + * Either increments the count of the number of occurrences of the + * encountered null or Boolean value or classifies a source element + * as containing the {@code eval} identifier name. + * @param {string} sIdentifier The identifier encountered. + */ + 'name': function(sIdentifier) { + if (-1 !== A_OTHER_SUBSTITUTABLE_LITERALS.indexOf(sIdentifier)) { + fCountPrimaryExpression( + EPrimaryExpressionCategories.N_NULL_AND_BOOLEAN_LITERALS, + EValuePrefixes.S_SYMBOLIC + sIdentifier); + } else { + if ('eval' === sIdentifier) { + oSourceElementData.nCategory = + ESourceElementCategories.N_EVAL; + } + fAddIdentifier(sIdentifier); + } + }, + /** + * Classifies the source element as excludable if it does not + * contain a {@code with} statement or the {@code eval} identifier + * name. + * @param {TSyntacticCodeUnit} oExpression The expression whose + * value is to be returned. + */ + 'return': function(oExpression) { + fClassifyAsExcludable(); + }, + /** + * Increments the count of the number of occurrences of the + * encountered String value. + * @param {string} sStringValue The String value of the string + * literal encountered. + */ + 'string': function(sStringValue) { + if (sStringValue.length > 0) { + fCountPrimaryExpression( + EPrimaryExpressionCategories.N_STRING_LITERALS, + EValuePrefixes.S_STRING + sStringValue); + } + }, + /** + * Adds the identifier reserved for an exception to the list of + * identifier names found. + * @param {!TSyntacticCodeUnit} oTry A block of code in which an + * exception can occur. + * @param {Array} aCatch The identifier reserved for an exception + * and a block of code to handle the exception. + * @param {TSyntacticCodeUnit} oFinally An optional block of code + * to be evaluated regardless of whether an exception occurs. + */ + 'try': function(oTry, aCatch, oFinally) { + if (Array.isArray(aCatch)) { + fAddIdentifier(aCatch[0]); + } + }, + /** + * Classifies the source element as excludable if it does not + * contain a {@code with} statement or the {@code eval} identifier + * name. Adds the identifier of each declared variable to the list + * of identifier names found. + * @param {!Array.<!Array>} aVariableDeclarationList Variable + * declarations. + */ + 'var': function(aVariableDeclarationList) { + fClassifyAsExcludable(); + aVariableDeclarationList.forEach(fAddVariable); + }, + /** + * Classifies a source element as containing the {@code with} + * statement. + * @param {!TSyntacticCodeUnit} oExpression An expression whose + * value is to be converted to a value of type Object and + * become the binding object of a new object environment + * record of a new lexical environment in which the statement + * is to be executed. + * @param {!TSyntacticCodeUnit} oStatement The statement to be + * executed in the augmented lexical environment. + * @return {!Array} An empty array to stop the traversal. + */ + 'with': function(oExpression, oStatement) { + oSourceElementData.nCategory = ESourceElementCategories.N_WITH; + return []; + } + /**#nocode-*/ // JsDoc Toolkit 2.4.0 hides some of the keys. + }, + /** + * A collection of functions used while looking for nested functions. + * @namespace + * @type {!Object.<string, function(...[*])>} + */ + oExamineFunctions: { + /**#nocode+*/ // JsDoc Toolkit 2.4.0 hides some of the keys. + /** + * Orders an examination of a nested function declaration. + * @this {!TSyntacticCodeUnit} An array-like object representing + * the branch of an <abbr title="abstract syntax tree" + * >AST</abbr> representing the syntactic code unit along with + * its scope. + * @return {!Array} An empty array to stop the traversal. + */ + 'defun': function() { + fExamineSyntacticCodeUnit(this); + return []; + }, + /** + * Orders an examination of a nested function expression. + * @this {!TSyntacticCodeUnit} An array-like object representing + * the branch of an <abbr title="abstract syntax tree" + * >AST</abbr> representing the syntactic code unit along with + * its scope. + * @return {!Array} An empty array to stop the traversal. + */ + 'function': function() { + fExamineSyntacticCodeUnit(this); + return []; + } + /**#nocode-*/ // JsDoc Toolkit 2.4.0 hides some of the keys. + } + }, + /** + * Records containing data about source elements. + * @type {Array.<TSourceElementsData>} + */ + aSourceElementsData = [], + /** + * The index (in the source text order) of the source element + * immediately following a <a href="http://es5.github.com/#x14.1" + * >Directive Prologue</a>. + * @type {number} + */ + nAfterDirectivePrologue = 0, + /** + * The index (in the source text order) of the source element that is + * currently being considered. + * @type {number} + */ + nPosition, + /** + * The index (in the source text order) of the source element that is + * the last element of the range of source elements that is currently + * being considered. + * @type {(undefined|number)} + */ + nTo, + /** + * Initiates the traversal of a source element. + * @param {!TWalker} oWalker An instance of an object that allows the + * traversal of an abstract syntax tree. + * @param {!TSyntacticCodeUnit} oSourceElement A source element from + * which the traversal should commence. + * @return {function(): !TSyntacticCodeUnit} A function that is able to + * initiate the traversal from a given source element. + */ + cContext = function(oWalker, oSourceElement) { + /** + * @return {!TSyntacticCodeUnit} A function that is able to + * initiate the traversal from a given source element. + */ + var fLambda = function() { + return oWalker.walk(oSourceElement); + }; + + return fLambda; + }, + /** + * Classifies the source element as excludable if it does not + * contain a {@code with} statement or the {@code eval} identifier + * name. + */ + fClassifyAsExcludable = function() { + if (oSourceElementData.nCategory === + ESourceElementCategories.N_OTHER) { + oSourceElementData.nCategory = + ESourceElementCategories.N_EXCLUDABLE; + } + }, + /** + * Adds an identifier to the list of identifier names found. + * @param {string} sIdentifier The identifier to be added. + */ + fAddIdentifier = function(sIdentifier) { + if (-1 === oSourceElementData.aIdentifiers.indexOf(sIdentifier)) { + oSourceElementData.aIdentifiers.push(sIdentifier); + } + }, + /** + * Adds the identifier of a variable to the list of identifier names + * found. + * @param {!Array} aVariableDeclaration A variable declaration. + */ + fAddVariable = function(aVariableDeclaration) { + fAddIdentifier(/** @type {string} */ aVariableDeclaration[0]); + }, + /** + * Increments the count of the number of occurrences of the prefixed + * String representation attributed to the primary expression. + * @param {number} nCategory The category of the primary expression. + * @param {string} sName The prefixed String representation attributed + * to the primary expression. + */ + fCountPrimaryExpression = function(nCategory, sName) { + if (!oSourceElementData.aCount[nCategory].hasOwnProperty(sName)) { + oSourceElementData.aCount[nCategory][sName] = 0; + if (-1 === oSourceElementData.aPrimitiveValues.indexOf(sName)) { + oSourceElementData.aPrimitiveValues.push(sName); + } + } + oSourceElementData.aCount[nCategory][sName] += 1; + }, + /** + * Consolidates all worthwhile primitive values in a range of source + * elements. + * @param {number} nFrom The index (in the source text order) of the + * source element that is the first element of the range. + * @param {number} nTo The index (in the source text order) of the + * source element that is the last element of the range. + * @param {boolean} bEnclose Indicates whether the range should be + * enclosed within a function call with no argument values to a + * function with an empty parameter list if any primitive values + * are consolidated. + * @see TPrimitiveValue#nSaving + */ + fExamineSourceElements = function(nFrom, nTo, bEnclose) { + var _, + /** + * The index of the last mangled name. + * @type {number} + */ + nIndex = oScope.cname, + /** + * The index of the source element that is currently being + * considered. + * @type {number} + */ + nPosition, + /** + * A collection of functions used during the consolidation of + * primitive values and identifier names used as property + * accessors. + * @namespace + * @type {!Object.<string, function(...[*])>} + */ + oWalkersTransformers = { + /** + * If the String value that is equivalent to the sequence of + * terminal symbols that constitute the encountered identifier + * name is worthwhile, a syntactic conversion from the dot + * notation to the bracket notation ensues with that sequence + * being substituted by an identifier name to which the value + * is assigned. + * Applies to property accessors that use the dot notation. + * @param {!TSyntacticCodeUnit} oExpression The nonterminal + * MemberExpression. + * @param {string} sIdentifierName The identifier name used as + * the property accessor. + * @return {!Array} A syntactic code unit that is equivalent to + * the one encountered. + * @see TPrimitiveValue#nSaving + */ + 'dot': function(oExpression, sIdentifierName) { + /** + * The prefixed String value that is equivalent to the + * sequence of terminal symbols that constitute the + * encountered identifier name. + * @type {string} + */ + var sPrefixed = EValuePrefixes.S_STRING + sIdentifierName; + + return oSolutionBest.oPrimitiveValues.hasOwnProperty( + sPrefixed) && + oSolutionBest.oPrimitiveValues[sPrefixed].nSaving > 0 ? + ['sub', + oWalker.walk(oExpression), + ['name', + oSolutionBest.oPrimitiveValues[sPrefixed].sName]] : + ['dot', oWalker.walk(oExpression), sIdentifierName]; + }, + /** + * If the encountered identifier is a null or Boolean literal + * and its value is worthwhile, the identifier is substituted + * by an identifier name to which that value is assigned. + * Applies to identifier names. + * @param {string} sIdentifier The identifier encountered. + * @return {!Array} A syntactic code unit that is equivalent to + * the one encountered. + * @see TPrimitiveValue#nSaving + */ + 'name': function(sIdentifier) { + /** + * The prefixed representation String of the identifier. + * @type {string} + */ + var sPrefixed = EValuePrefixes.S_SYMBOLIC + sIdentifier; + + return [ + 'name', + oSolutionBest.oPrimitiveValues.hasOwnProperty(sPrefixed) && + oSolutionBest.oPrimitiveValues[sPrefixed].nSaving > 0 ? + oSolutionBest.oPrimitiveValues[sPrefixed].sName : + sIdentifier + ]; + }, + /** + * If the encountered String value is worthwhile, it is + * substituted by an identifier name to which that value is + * assigned. + * Applies to String values. + * @param {string} sStringValue The String value of the string + * literal encountered. + * @return {!Array} A syntactic code unit that is equivalent to + * the one encountered. + * @see TPrimitiveValue#nSaving + */ + 'string': function(sStringValue) { + /** + * The prefixed representation String of the primitive value + * of the literal. + * @type {string} + */ + var sPrefixed = + EValuePrefixes.S_STRING + sStringValue; + + return oSolutionBest.oPrimitiveValues.hasOwnProperty( + sPrefixed) && + oSolutionBest.oPrimitiveValues[sPrefixed].nSaving > 0 ? + ['name', + oSolutionBest.oPrimitiveValues[sPrefixed].sName] : + ['string', sStringValue]; + } + }, + /** + * Such data on what to consolidate within the range of source + * elements that is currently being considered that lead to the + * greatest known reduction of the number of the terminal symbols + * in comparison to the original source text. + * @type {!TSolution} + */ + oSolutionBest = new TSolution(), + /** + * Data representing an ongoing attempt to find a better + * reduction of the number of the terminal symbols in comparison + * to the original source text than the best one that is + * currently known. + * @type {!TSolution} + * @see oSolutionBest + */ + oSolutionCandidate = new TSolution(), + /** + * A record consisting of data about the range of source elements + * that is currently being examined. + * @type {!TSourceElementsData} + */ + oSourceElementsData = new TSourceElementsData(), + /** + * Variable declarations for each primitive value that is to be + * consolidated within the elements. + * @type {!Array.<!Array>} + */ + aVariableDeclarations = [], + /** + * Augments a list with a prefixed representation String. + * @param {!Array.<string>} aList A list that is to be augmented. + * @return {function(string)} A function that augments a list + * with a prefixed representation String. + */ + cAugmentList = function(aList) { + /** + * @param {string} sPrefixed Prefixed representation String of + * a primitive value that could be consolidated within the + * elements. + */ + var fLambda = function(sPrefixed) { + if (-1 === aList.indexOf(sPrefixed)) { + aList.push(sPrefixed); + } + }; + + return fLambda; + }, + /** + * Adds the number of occurrences of a primitive value of a given + * category that could be consolidated in the source element with + * a given index to the count of occurrences of that primitive + * value within the range of source elements that is currently + * being considered. + * @param {number} nPosition The index (in the source text order) + * of a source element. + * @param {number} nCategory The category of the primary + * expression from which the primitive value is derived. + * @return {function(string)} A function that performs the + * addition. + * @see cAddOccurrencesInCategory + */ + cAddOccurrences = function(nPosition, nCategory) { + /** + * @param {string} sPrefixed The prefixed representation String + * of a primitive value. + */ + var fLambda = function(sPrefixed) { + if (!oSourceElementsData.aCount[nCategory].hasOwnProperty( + sPrefixed)) { + oSourceElementsData.aCount[nCategory][sPrefixed] = 0; + } + oSourceElementsData.aCount[nCategory][sPrefixed] += + aSourceElementsData[nPosition].aCount[nCategory][ + sPrefixed]; + }; + + return fLambda; + }, + /** + * Adds the number of occurrences of each primitive value of a + * given category that could be consolidated in the source + * element with a given index to the count of occurrences of that + * primitive values within the range of source elements that is + * currently being considered. + * @param {number} nPosition The index (in the source text order) + * of a source element. + * @return {function(number)} A function that performs the + * addition. + * @see fAddOccurrences + */ + cAddOccurrencesInCategory = function(nPosition) { + /** + * @param {number} nCategory The category of the primary + * expression from which the primitive value is derived. + */ + var fLambda = function(nCategory) { + Object.keys( + aSourceElementsData[nPosition].aCount[nCategory] + ).forEach(cAddOccurrences(nPosition, nCategory)); + }; + + return fLambda; + }, + /** + * Adds the number of occurrences of each primitive value that + * could be consolidated in the source element with a given index + * to the count of occurrences of that primitive values within + * the range of source elements that is currently being + * considered. + * @param {number} nPosition The index (in the source text order) + * of a source element. + */ + fAddOccurrences = function(nPosition) { + Object.keys(aSourceElementsData[nPosition].aCount).forEach( + cAddOccurrencesInCategory(nPosition)); + }, + /** + * Creates a variable declaration for a primitive value if that + * primitive value is to be consolidated within the elements. + * @param {string} sPrefixed Prefixed representation String of a + * primitive value that could be consolidated within the + * elements. + * @see aVariableDeclarations + */ + cAugmentVariableDeclarations = function(sPrefixed) { + if (oSolutionBest.oPrimitiveValues[sPrefixed].nSaving > 0) { + aVariableDeclarations.push([ + oSolutionBest.oPrimitiveValues[sPrefixed].sName, + [0 === sPrefixed.indexOf(EValuePrefixes.S_SYMBOLIC) ? + 'name' : 'string', + sPrefixed.substring(EValuePrefixes.S_SYMBOLIC.length)] + ]); + } + }, + /** + * Sorts primitive values with regard to the difference in the + * number of terminal symbols between the original source text + * and the one with those primitive values consolidated. + * @param {string} sPrefixed0 The prefixed representation String + * of the first of the two primitive values that are being + * compared. + * @param {string} sPrefixed1 The prefixed representation String + * of the second of the two primitive values that are being + * compared. + * @return {number} + * <dl> + * <dt>-1</dt> + * <dd>if the first primitive value must be placed before + * the other one,</dd> + * <dt>0</dt> + * <dd>if the first primitive value may be placed before + * the other one,</dd> + * <dt>1</dt> + * <dd>if the first primitive value must not be placed + * before the other one.</dd> + * </dl> + * @see TSolution.oPrimitiveValues + */ + cSortPrimitiveValues = function(sPrefixed0, sPrefixed1) { + /** + * The difference between: + * <ol> + * <li>the difference in the number of terminal symbols + * between the original source text and the one with the + * first primitive value consolidated, and</li> + * <li>the difference in the number of terminal symbols + * between the original source text and the one with the + * second primitive value consolidated.</li> + * </ol> + * @type {number} + */ + var nDifference = + oSolutionCandidate.oPrimitiveValues[sPrefixed0].nSaving - + oSolutionCandidate.oPrimitiveValues[sPrefixed1].nSaving; + + return nDifference > 0 ? -1 : nDifference < 0 ? 1 : 0; + }, + /** + * Assigns an identifier name to a primitive value and calculates + * whether instances of that primitive value are worth + * consolidating. + * @param {string} sPrefixed The prefixed representation String + * of a primitive value that is being evaluated. + */ + fEvaluatePrimitiveValue = function(sPrefixed) { + var _, + /** + * The index of the last mangled name. + * @type {number} + */ + nIndex, + /** + * The representation String of the primitive value that is + * being evaluated. + * @type {string} + */ + sName = + sPrefixed.substring(EValuePrefixes.S_SYMBOLIC.length), + /** + * The number of source characters taken up by the + * representation String of the primitive value that is + * being evaluated. + * @type {number} + */ + nLengthOriginal = sName.length, + /** + * The number of source characters taken up by the + * identifier name that could substitute the primitive + * value that is being evaluated. + * substituted. + * @type {number} + */ + nLengthSubstitution, + /** + * The number of source characters taken up by by the + * representation String of the primitive value that is + * being evaluated when it is represented by a string + * literal. + * @type {number} + */ + nLengthString = oProcessor.make_string(sName).length; + + oSolutionCandidate.oPrimitiveValues[sPrefixed] = + new TPrimitiveValue(); + do { // Find an identifier unused in this or any nested scope. + nIndex = oScope.cname; + oSolutionCandidate.oPrimitiveValues[sPrefixed].sName = + oScope.next_mangled(); + } while (-1 !== oSourceElementsData.aIdentifiers.indexOf( + oSolutionCandidate.oPrimitiveValues[sPrefixed].sName)); + nLengthSubstitution = oSolutionCandidate.oPrimitiveValues[ + sPrefixed].sName.length; + if (0 === sPrefixed.indexOf(EValuePrefixes.S_SYMBOLIC)) { + // foo:null, or foo:null; + oSolutionCandidate.oPrimitiveValues[sPrefixed].nSaving -= + nLengthSubstitution + nLengthOriginal + + oWeights.N_VARIABLE_DECLARATION; + // null vs foo + oSolutionCandidate.oPrimitiveValues[sPrefixed].nSaving += + oSourceElementsData.aCount[ + EPrimaryExpressionCategories. + N_NULL_AND_BOOLEAN_LITERALS][sPrefixed] * + (nLengthOriginal - nLengthSubstitution); + } else { + // foo:'fromCharCode'; + oSolutionCandidate.oPrimitiveValues[sPrefixed].nSaving -= + nLengthSubstitution + nLengthString + + oWeights.N_VARIABLE_DECLARATION; + // .fromCharCode vs [foo] + if (oSourceElementsData.aCount[ + EPrimaryExpressionCategories.N_IDENTIFIER_NAMES + ].hasOwnProperty(sPrefixed)) { + oSolutionCandidate.oPrimitiveValues[sPrefixed].nSaving += + oSourceElementsData.aCount[ + EPrimaryExpressionCategories.N_IDENTIFIER_NAMES + ][sPrefixed] * + (nLengthOriginal - nLengthSubstitution - + oWeights.N_PROPERTY_ACCESSOR); + } + // 'fromCharCode' vs foo + if (oSourceElementsData.aCount[ + EPrimaryExpressionCategories.N_STRING_LITERALS + ].hasOwnProperty(sPrefixed)) { + oSolutionCandidate.oPrimitiveValues[sPrefixed].nSaving += + oSourceElementsData.aCount[ + EPrimaryExpressionCategories.N_STRING_LITERALS + ][sPrefixed] * + (nLengthString - nLengthSubstitution); + } + } + if (oSolutionCandidate.oPrimitiveValues[sPrefixed].nSaving > + 0) { + oSolutionCandidate.nSavings += + oSolutionCandidate.oPrimitiveValues[sPrefixed].nSaving; + } else { + oScope.cname = nIndex; // Free the identifier name. + } + }, + /** + * Adds a variable declaration to an existing variable statement. + * @param {!Array} aVariableDeclaration A variable declaration + * with an initialiser. + */ + cAddVariableDeclaration = function(aVariableDeclaration) { + (/** @type {!Array} */ oSourceElements[nFrom][1]).unshift( + aVariableDeclaration); + }; + + if (nFrom > nTo) { + return; + } + // If the range is a closure, reuse the closure. + if (nFrom === nTo && + 'stat' === oSourceElements[nFrom][0] && + 'call' === oSourceElements[nFrom][1][0] && + 'function' === oSourceElements[nFrom][1][1][0]) { + fExamineSyntacticCodeUnit(oSourceElements[nFrom][1][1]); + return; + } + // Create a list of all derived primitive values within the range. + for (nPosition = nFrom; nPosition <= nTo; nPosition += 1) { + aSourceElementsData[nPosition].aPrimitiveValues.forEach( + cAugmentList(oSourceElementsData.aPrimitiveValues)); + } + if (0 === oSourceElementsData.aPrimitiveValues.length) { + return; + } + for (nPosition = nFrom; nPosition <= nTo; nPosition += 1) { + // Add the number of occurrences to the total count. + fAddOccurrences(nPosition); + // Add identifiers of this or any nested scope to the list. + aSourceElementsData[nPosition].aIdentifiers.forEach( + cAugmentList(oSourceElementsData.aIdentifiers)); + } + // Distribute identifier names among derived primitive values. + do { // If there was any progress, find a better distribution. + oSolutionBest = oSolutionCandidate; + if (Object.keys(oSolutionCandidate.oPrimitiveValues).length > 0) { + // Sort primitive values descending by their worthwhileness. + oSourceElementsData.aPrimitiveValues.sort(cSortPrimitiveValues); + } + oSolutionCandidate = new TSolution(); + oSourceElementsData.aPrimitiveValues.forEach( + fEvaluatePrimitiveValue); + oScope.cname = nIndex; + } while (oSolutionCandidate.nSavings > oSolutionBest.nSavings); + // Take the necessity of adding a variable statement into account. + if ('var' !== oSourceElements[nFrom][0]) { + oSolutionBest.nSavings -= oWeights.N_VARIABLE_STATEMENT_AFFIXATION; + } + if (bEnclose) { + // Take the necessity of forming a closure into account. + oSolutionBest.nSavings -= oWeights.N_CLOSURE; + } + if (oSolutionBest.nSavings > 0) { + // Create variable declarations suitable for UglifyJS. + Object.keys(oSolutionBest.oPrimitiveValues).forEach( + cAugmentVariableDeclarations); + // Rewrite expressions that contain worthwhile primitive values. + for (nPosition = nFrom; nPosition <= nTo; nPosition += 1) { + oWalker = oProcessor.ast_walker(); + oSourceElements[nPosition] = + oWalker.with_walkers( + oWalkersTransformers, + cContext(oWalker, oSourceElements[nPosition])); + } + if ('var' === oSourceElements[nFrom][0]) { // Reuse the statement. + (/** @type {!Array.<!Array>} */ aVariableDeclarations.reverse( + )).forEach(cAddVariableDeclaration); + } else { // Add a variable statement. + Array.prototype.splice.call( + oSourceElements, + nFrom, + 0, + ['var', aVariableDeclarations]); + nTo += 1; + } + if (bEnclose) { + // Add a closure. + Array.prototype.splice.call( + oSourceElements, + nFrom, + 0, + ['stat', ['call', ['function', null, [], []], []]]); + // Copy source elements into the closure. + for (nPosition = nTo + 1; nPosition > nFrom; nPosition -= 1) { + Array.prototype.unshift.call( + oSourceElements[nFrom][1][1][3], + oSourceElements[nPosition]); + } + // Remove source elements outside the closure. + Array.prototype.splice.call( + oSourceElements, + nFrom + 1, + nTo - nFrom + 1); + } + } + if (bEnclose) { + // Restore the availability of identifier names. + oScope.cname = nIndex; + } + }; + + oSourceElements = (/** @type {!TSyntacticCodeUnit} */ + oSyntacticCodeUnit[bIsGlobal ? 1 : 3]); + if (0 === oSourceElements.length) { + return; + } + oScope = bIsGlobal ? oSyntacticCodeUnit.scope : oSourceElements.scope; + // Skip a Directive Prologue. + while (nAfterDirectivePrologue < oSourceElements.length && + 'directive' === oSourceElements[nAfterDirectivePrologue][0]) { + nAfterDirectivePrologue += 1; + aSourceElementsData.push(null); + } + if (oSourceElements.length === nAfterDirectivePrologue) { + return; + } + for (nPosition = nAfterDirectivePrologue; + nPosition < oSourceElements.length; + nPosition += 1) { + oSourceElementData = new TSourceElementsData(); + oWalker = oProcessor.ast_walker(); + // Classify a source element. + // Find its derived primitive values and count their occurrences. + // Find all identifiers used (including nested scopes). + oWalker.with_walkers( + oWalkers.oSurveySourceElement, + cContext(oWalker, oSourceElements[nPosition])); + // Establish whether the scope is still wholly examinable. + bIsWhollyExaminable = bIsWhollyExaminable && + ESourceElementCategories.N_WITH !== oSourceElementData.nCategory && + ESourceElementCategories.N_EVAL !== oSourceElementData.nCategory; + aSourceElementsData.push(oSourceElementData); + } + if (bIsWhollyExaminable) { // Examine the whole scope. + fExamineSourceElements( + nAfterDirectivePrologue, + oSourceElements.length - 1, + false); + } else { // Examine unexcluded ranges of source elements. + for (nPosition = oSourceElements.length - 1; + nPosition >= nAfterDirectivePrologue; + nPosition -= 1) { + oSourceElementData = (/** @type {!TSourceElementsData} */ + aSourceElementsData[nPosition]); + if (ESourceElementCategories.N_OTHER === + oSourceElementData.nCategory) { + if ('undefined' === typeof nTo) { + nTo = nPosition; // Indicate the end of a range. + } + // Examine the range if it immediately follows a Directive Prologue. + if (nPosition === nAfterDirectivePrologue) { + fExamineSourceElements(nPosition, nTo, true); + } + } else { + if ('undefined' !== typeof nTo) { + // Examine the range that immediately follows this source element. + fExamineSourceElements(nPosition + 1, nTo, true); + nTo = void 0; // Obliterate the range. + } + // Examine nested functions. + oWalker = oProcessor.ast_walker(); + oWalker.with_walkers( + oWalkers.oExamineFunctions, + cContext(oWalker, oSourceElements[nPosition])); + } + } + } + }(oAbstractSyntaxTree = oProcessor.ast_add_scope(oAbstractSyntaxTree))); + return oAbstractSyntaxTree; +}; +/*jshint sub:false */ + +/* Local Variables: */ +/* mode: js */ +/* coding: utf-8 */ +/* indent-tabs-mode: nil */ +/* tab-width: 2 */ +/* End: */ +/* vim: set ft=javascript fenc=utf-8 et ts=2 sts=2 sw=2: */ +/* :mode=javascript:noTabs=true:tabSize=2:indentSize=2:deepIndent=true: */
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